1. Field of the Invention
The present invention relates generally to a vacuum cleaner, and more particularly to a cyclone dust collecting apparatus for a vacuum cleaner that centrifugally separates an air drawn into with a dust on a cleaning surface.
2. Description of the Related Art
Generally, a vacuum cleaner having a cyclone dust collecting apparatus includes a cleaner body, a suction unit, and the cyclone dust collecting apparatus. The cyclone dust collecting apparatus includes a cyclone body, a suction pipe, a discharge pipe, and a dust collector. The cyclone body provides a space for air drawn into the cyclone body from outside through the suction pipe to centrifugally separate the dust entrained in the air, and centrifugally separated clean air is discharged to outside of the cyclone body through the discharge pipe. The dust collector is connected to a lower end of the cyclone body and is used to collect the dust separated from the air.
The operation of a conventional cyclone dust collecting apparatus 20 will be described with reference to FIG. 1.
The air drawn from the surface to be cleaned is drawn by a suction unit (not shown) into the cyclone body 21 through the suction pipe 27. The air guided into the cyclone body 21 flows downwardly by whirling along a side wall of the cyclone body 21, as shown by the arrows. The current velocity of some of the air whirling near to the side wall of the cyclone body 21 decreases due to the fluid friction with the side wall. Accordingly, dust, which is entrained in the air, comes into contact with the side wall of the cyclone body 21 due to a centrifugal force of the air, becomes slower moving and is collected by gravitation in the dust collector 23 connected with a lower part of the cyclone body 21 by falling downwardly along the side wall of the cyclone body 21.
On the other hand, as described above, the air backflows upwardly again after reaching the bottom 23a of the dust collector 23. The current velocity of the flowing air at the bottom 23a of the dust collector 23 is minimized when the air reaches the bottom 23a in the cyclone dust collecting apparatus 20. Therefore, fine dust entrained in the air that backflows upwardly becomes separated, and the fine dust is collected with the dust previously collected at the bottom 23a of the dust collector 23. The clean air from which the dust has been removed is discharged to the outside of the cyclone body 21 through the discharge pipe 25.
However, although the current velocity of the air at the bottom 23a of the dust collector 23 is minimized, the air whirls at a low velocity at the bottom 23a by the effect of the centrifugal force generated before reaching the bottom 23a after the dust is separated. Accordingly, the dust collected at the bottom 23a continuously flows since the dust is not stabilized. The fine dust collected at the bottom 23a may again be picked up by the flowing air together with other dust, such as a hair of a person or an animal. In addition, when a large amount of dust is collected in the dust collector 23, such reflow of dust is aggravated.
Therefore, as described above, in a conventional cyclone dust collecting apparatus 20, the problem of dust backflow phenomenon results in flowing dust being discharged to the outside with the clean air through the discharge pipe 25.
An object of the present invention is to provide a cyclone dust collecting apparatus for a vacuum cleaner having an improved structure for dust collection by preventing dust, which is collected after being centrifugally separated from the air in the cyclone body, from again becoming entrained in the air stream.
The above object is accomplished by providing a cyclone dust collecting apparatus including: a cylindrical-type cyclone body for centrifugally separating dust entrained in air drawn into the cylindrical-type cyclone body from outside through a suction pipe and discharging clean air through a discharge pipe; a dust collector disposed at a lower part of the cyclone body in order to collect a dust centrifugally separated from the air; and a plurality of dust backflow and rotation prevention members protruded from a bottom of the dust collector for a predetermined length.
In addition, it is preferable that the dust backflow and rotation prevention members comprise pillars-having a non-circular cross-sectional area.
Moreover, it is advisable that the dust backflow and rotation prevention members are disposed radially at the bottom of the dust collector to have a predetermined distance from the center of the bottom, and to have the same angle with a predetermined degree of separation relative to each other.
It is more preferable that the dust backflow and rotation prevention members protrude from the bottom of the dust collector with a ratio of xc2xc to {fraction (1/2 )} relative to the height of the dust collector.
According to the cyclone dust collecting apparatus of the present invention having the above construction, the dust collected at the bottom of the dust collector is prevented from becoming entrained in the whirling clean air stream. Therefore, the dust in the dust collector is inhibited from being backflown to the discharge pipe with the clean air.